Production of Tuberose (Polianthes tuberosa L.) as Affected by Bulb Size and Planting Medium

IntroductionT uberose (Polianthes tuberosa L.) is among commercial cut flowers.It belongs to family Amaryllidacea and is originated from Mexico.It is commercially used in landscape gardening and in the floriculture industry throughout the world.It is mostly grown in Morocco, France, Hawaii, South Africa, India and China (Naznin et al., 2015).It is used for table purpose as cut flower because it has long spike length, long post-harvest life and extremely fragrance.It is commercially used for garland making, aesthetic purpose, birthday ceremony, floral arrangement such as; bouquets and in perfumes (Qureshi et al., 2018;Ali et al., 2019).It is also used in beverages and pharmaceuticals industry (Mandal et al., 2018).Tuberose gives nice flowers in summer and autumn.Different sizes of bulbs affect the production and quality of tuberose flowers (Raja and Palanisamy, 1999;Aksu and Celikel, 2003).There is serious concern on Abstract | Tuberose is an important element of a landscape garden.It is placed among top ten cut flowers in floriculture industry.Quality production of cut flowers for market depends upon bulb size and growing medium.To investigate the best type of planting medium and suitable bulb size for commercial production of tuberose, an experiment was conducted in the Horticulture Nursery, University of Swabi, Pakistan in the year 2019.Three bulb sizes of tuberose viz., large (2.5cm dia), medium (1.5cm dia) and small (1cm dia) were planted in three type of planting media viz., M1(Sandy soil+ Compost; 3:1; v/v), M2 (Sandy soil+ Humic acid; 20:1; v/v) and M3 (Sandy soil + Potting soil; 3:1; v/v) in Randomized Complete Block Design (RCBD) with 3 replications.Significant differences were found in all the agronomic and floral characteristics of tuberose for both planting medium and bulb sizes.Tallest (43.08 cm) plants, maximum number of leaves plant -1 (22.17), florets spike -1 (22.79) and number of bulblets produced plant -1 (22.03) were found in soil amended with humic acid.However, the least days (85.22) to flowering were observed in planting medium amended with potting soil and largest bulblets (2.14cm) were found in compost amended sandy soil.As far as the effect of bulb size is concerned, maximum days to flowering (97.44), plant height (43.29cm), number of leaves (24.54), number of florets (19.17), bulblets plant -1 (24.30) and bulblet diameter (2.08 cm) were produced by growing large sized bulbs.